1. What does the esr of Firefox v52 mean? 2. Why is the version of Firefox downloaded from domestic websites always larger than that downloaded from official website?

Firefox esr is an extended support version of Firefox and a long-term support version. The normal maintenance cycle of the official version of Firefox is 6 weeks, and the maintenance cycle of esr is 42 weeks, that is, the official version is updated every 7 versions, and esr is updated once.

Domestic Firefox is customized by Mouzhi Company for domestic users. Compared with the original Firefox, it has more functions and extensions that are more suitable for China people. These features can be manually removed later. Firefox China version is consistent with the original version in security.